Fire-alarm.



11. T. RBICHEL.

FIRE ALARM. APPLICATION FILED DEC. 22, 1908.

Patented Apr. 11,1911.

ITN E5555;

UNITED s'rar is PATENT OFFICE.

LOUIS TASMAN REICHEL, OF WELLINGTON, NEW ZEALAND, ASSIGNOR TO THEREICHEL AUTOMATIC FIRE ALARM COMPANY, LIMITED, A CORPORATION OF NEWZEALAND.

FIRE-ALARM.

Specification of Letters Patent.

Patented Apr. 11', 1911.

Application filed December 22, 1908. Serial No. 468,800.

) This invention relates to nnproved means that have been devised forthe purpose of sounding an alarm upon a sudden rise of temperature, suchas would be occasioned by an outbreak of fire, taking place.

The invention is applicable to buildings, ships holds, mines or otherinclosed areas, and may be arranged to sound an alarm at anydistance'away from such area.

The invention consists in the utilization of a thermopile to produce-acurrent of elec.

tricity sufliciently strong to actuate a galvanometer which, in turn,will cause an electric alarm circuit to be closed when the galvanometerpointer has been deflected a certain regulated distance.

The thermopile will be so constructed that it may be secured upona-ceiling or wall of a building, and any desired number of suchthermopiles may be arranged in series with the galvanometer. Thethermopile will be also so formed that a current of suflicient strengthto actuate the galvanometer pointer the required amount, will only begenerated upon a sudden rise of temperature occurring in' its vicinity.

In order, however, that the invention may be properly understood,reference will be made to the accompanying sheet of drawngs, in Which,--

Figure 1 is a diagram illustrating the ar- 7 rangement of the parts andcircuits making up the alarm. Figs. 2 and 3 are respectively plan andsectional elevation of an approved form of thermopile for use inconjunction with this invention. Fig. 4 is a diagram of an alternativearrangement of circuits in which provision is made for the ringing of abell should the thermopile circuit,

through any cause be broken, and also for the closing of the fire alarmcircuit upon the surrounding temperature reaching any .predetermineddegree (whether the rise of temperature be slow or fast).

In carrying out the invention, a galvanometer a preferably of the movingcoil type, is placed at any desired point, and a number of thermopiles bare arranged around the room, or throughout a number of rooms if sodesired. These thermopiles are arranged in series circuit with thegalvanometer, so that upon a current being created in anyone of them,the pointer of the galvanometer will be deflected proportionately withthe strength of the current.

Arranged in a position adjacent to the lower end of the galvanometerpointer, is an adjustable terminal 0 arranged in circuit with a batteryd and a bell e, such battery and bell being also arranged to completecircuit through the galvanometer pointer, when the pointer is deflectedsufiiciently to cause it tomoveover and engage with the terminal 0, themoving coil being connected to the pointer. The alarm circuit will thenbe completed, and the bell caused to sound. The terminal 0 ofnon-magnetic material is preferably formed as part of, or attached to apermanent magnet f, which will serve to pull the galvanometer pointerinto'close contact with the terminal when it moves to a position withinthe influence of the magnet. For this purpose, the end of such pointerwill be made of iron. Thus, an effectual contact is assured, and anyliability.

of such contact being hindered by the pressure of dust upon the points,prevented.

In order to provide for the testing of the installation at any time, abattery g (Fig h. Suitable resistances j are provided,"

whereby the current sent through this circuit may be weakened to suchadegree as to prevent injury to the galvanometer. Instead of the battery,a thermopile may be employed to generate the desired current.

The form of thermopile shown in the drawings consists of a base piece kof wood or other non-conductin material, to the surface'of which acasing m is attached. Within the casing is arranged a disk 12. ofplaster of Paris or other like plastic insulating material in which areembedded a number of cores 0- of two different metals connected togetheron the well known thermopile principle. The metals preferably employedin this invention are bismuth and Clammond alloy or antimony, which havehigh thermo-electric values. These cores are so arranged that theirouter ends will project beyond the outer surface of the disk 11. whiletheir inner ends will lie behind such disk. Consequently, the outer endswill be fully exposed to the sudden heat given off by an outburst offlames while the inner ends will'be protected therefrom, thus causingthe thermo current to be generated.

By using in the thermopiles, metals such as bismuth, antimony, Clammondalloy, or nickel, which have a high thermo-e'lectric value, and at thesame time making the blocks of metal short and thick, thereby reduringthe internal electrical resistance of the thermopiles, in combinationwith a low resistance galvanometer, a few degrees sudden rise oftemperature will cause sufiicient flow of current to operate the alarm.

Any gradual rise in the temperature will cause the whole appliance to beheated so that no current will be generated, or at most,

\, only a slight one not suflicient to deflect the galvanometer pointerthe required amount to close the alarm circuit. If necessary "for thispurpose, the sides of the casing m may have apertures 1' formed inthemto allow of the surrounding atmosphere having free access to the backends of the cores 0 and p.

In order to provide against false alarms, caused by the gas or otherlight being lighted in a room, a scale is fixed under the galvanometerpointer, and serves to show the amount of deflection thereof. Thedeflections of the pointer due to variable changes of temperature willthereby serve as an indicator that the system is in good working .order,and willaalso serve to indicate the position to which theterminal 0 mustbe adjusted to provide for. the the system. I 4

The means shown in Fig. 4 for providing for an alarm being soundedshould the thermopile circuit bebroken, consist in arranging a battery 8in shunt circuit with the thermopile circuit, so as to send a currentpermanently through such circuit sufficiently strongto slightly deflectthe galvanometer pointer toward the terminal 0 as shown. The strength ofthis current is governed by suitable resistances. A second bell circuitzis arranged in circuit with the galvanometer polnter, and an adjustableterminal a arranged upon the opposite side of such pointer. Thisterminal u is so adjusted that when'the' pointer is at its normalposition, it will make contact therewith. Thus, should the thermopilecircuitbe broken, the galvanometer pointer will swing back .to itsnormal-position, thereby closing the bell cir-, cuit t and causln g suchbell to sound.

To provide for thealarm being sounded proper working of I when thetemperature surrounding the hermopiles has risen slowly to a certain xeddegree,'say for instance, in a ships hold in case of a smoldering fire,an adjustable thermometer w (Fig. 4) adapted to make known way, isarranged with a battery as in shunt circuit with the thermopile circuitThus, when the temperature rises to the predetermined degree, a currentwill be sent through the thermopile circuit, and the alarm circuitclosed in the manner before described. Any approved form of thermostatmay be employed in place of the thermome'ter.

It will be readily understood that a number of galvanometers may bearranged to operate the same alarm circuit, each one being in circuitwith a separate thermopile circuit. Thus, provision may be made for anindication being given as to the location of a fire in addition to thesounding of the alarm.

In describing the invention, an ordinary electric bell has beendescribed as part of the alarm circuit, but it will be readilyunderstood that other classes of 'sonorous sig- 'nals maybe employedwithout departing 1. In fire alarms, in combination, a thcr-' mopile, agalvanometer arranged in circuit with the thermopile, a pointer therein,a

terminal mounted adjacent to the galva nometer pointer, a magnet nearsuch terminal arranged to act on said pointer and a bell and batteryarranged to directly complete circuit with the galvanometer pointer andthe terminal.

2. In fire alarms, in combination, a thermopile, a galvanometer arrangedin circuit therewith, a battery, .9, arranged in shunt circuit with apart of the thermopile circuit adapted to send a slight currentpermanently through said circuit, a bell circuit adapted to be closed bythe movement of the galvanometer pointer in one direction, and asecondbell circuit adapted to be closed by the movement of said pointer in thereverse direction, substantially as herein specified.

3. In fire alarms, the combination with a thermopile, a galvanometerarranged in circuit therewith and a bell circuit adapted to be closed bythe movement of the galvanometer pointer, of a battery and thermostatarranged to complete a shunt'circuit with a portion of the thermopilecircuit, substantially as specified.

4. In fire alarms, in combination, a thermopile, a galvanometer arrangedin circuit with the thermopile, a magnet for, influencnometer when thatpointer is brought within the -field of the magnet, and a bell andbattery included in a circuit arranged to be directly closed by saidpointer.

5. In a fire alarm, a galvanometer needle, and a circuit for influencingmovement of the same, in combination with a ma et for also operating theneedle when the latter is brought within the field of said magthe fieldof the magnet, and an alarm means 10' net, an alarm means, and means,located in controlled by the movement of the'pointer. the path of andgoverned by the needle, for In testimony-whereof, I have signed'thiscontrolling the alarm means. specification in the presence of twosubscrib- 6. In fire alarms, ,in combination, a thering witnesses.

mopile, a galvanometer arranged in circuit LOUIS TASMAN REICHEL.

with the thermopile, a magnet for infiuenc- \Vitnesses:

ing movement of the pointer of the galva- H. ALEXANDER,

nometer when that pointer is brought within W. M. BORLASE.

